WCBD-TV (Charleston, SC)

WCBD-TV (Charleston, SC)
Background
WCBD-TV is the NBC-affiliated television station for the Low Country and Charleston
area of South Carolina and broadcasts a high definition digital signal from a transmitter in
Awendaw, South Carolina. The station is owned by Media General, Inc.
Challenge
The station’s transmitter site is located at the end of a utility cooperative line so sags
were a constant caused primarily by switching transients upstream from the site. Also,
crowbar events (10 millisecond short to ground of high voltage power supply) resulting
from sags or spikes would at times interrupt broadcasts and/or bring the transmitter site
down partly or completely, requiring a restart. This downtime would result in a loss in
advertising dollars and unplanned pay and time to dispatch a technician out to the site to
make repairs – 52 miles roundtrip and approximately one hour to make repairs. The
station at times could make 3-4 visits out to the site in a single week due at times to
power disturbances.
Solution
To achieve continuous, long term steady power and protect against crowbar events, the
station deployed an Active Power CleanSource 300 kVA UPS to protect the site’s
transmitter, transmitter studio links (TSL/STL), electronic news gathering (ENG)
microwaves, fiberoptics, and other critical electrical components. The parallel online
architecture of CleanSource UPS is uniquely designed to manage crowbar events and
the overloads and step loads typically seen with these events versus a legacy UPS with
batteries. CleanSource UPS will switch to bypass to supply desired current from the
lowest impedance source with no interruption to transmitters on the same circuit in the
event of an overload from a crowbar event.
Result
The flywheel UPS has experienced approximately 1,300 discharges since being
deployed in February in 2012 with no interruption to the transmitter site. In fact, trips out
to the site are rare except to conduct routine maintenance.
We are pleased with the operation of the UPS since its installation and
reliability of the transmitter. There is a lot to be said for equipment that
works right out of the box and that certainly is the case here.
– Art Smith, Chief Engineer
Confidential and Proprietary
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State Grid Corp of China – Beijing
Background
State Grid Corporation of China (SGCC) is the largest state owned utility in the
world responsible for the transmission and distribution of power across the
country via its subsidiaries. Headquartered in Beijing, the distributor is listed #7
on the Fortune 500 Global 2014 rankings.
Challenge
With the upcoming 2014 APEC (Asia Pacific Economic Cooperation) Forum in
Beijing, China Central Television (CCTV) would be responsible for constant,
uninterrupted broadcasting of all forum activities at multiple meeting venues
across the city including Beijing National Stadium. To support CCTV at these
broadcast sites, SGCC required a mobile critical power solution that could be
deployed and redeployed within hours; however, 10 m2 allocated for UPS made
for tight quarters in addition to lack of conditioned space.
Solution
SGCC, with the support of Active Power and its distributor Beijing Honest
Credibility Electric Technology Co., turned away from conventional approaches
to electrical design and creatively designed and built “flywheel trucks.” These
truck mounted modular power systems include Active Power’s CleanSource 500
kVA UPS and automatic transfer switch all installed in approximately 10 m2. The
500 kVA flywheel UPS consumes just 3.7 m2 compared to nearly 6 m2 for an
equivalent legacy UPS with four standard battery cabinets. Space and an
unconditioned environment deterred use of legacy UPS.
SGCC’s fleet of 17 trucks provided critical power support to CCTV’s broadcast
operations, lighting, and other critical equipment. These trucks leverage the
unique attributes of the flywheel UPS including industry leading power density in
a compact footprint, high reliability, and operating efficiencies of up to 98 percent.
Result
These mobile power solutions enabled CCTV to deliver on its promise of an
uninterrupted broadcast of APEC Forum events worldwide. Outside of APEC
Forum, these trucks have been used to support a number of national events and
have delivered temporary critical power following severe weather events.
Confidential and Proprietary
2
WFFF-TV / WVNY-TV (Burlington, VT)
Background
WFFF-TV (FOX) and WVNY-TV (ABC), properties of Nexstar Broadcasting,
serve major portions of Vermont, northern New Hampshire, and upstate New
York with significant viewership in Montreal. The station is located in Colchester,
VT, a suburb of Burlington.
Challenge
The stations had two specific goals as it embarked on building out their digital
television network – deliver the highest quality television service available and
create a reliable service infrastructure for its viewers with no interruptions. The
station also required a UPS system with very low maintenance.
Solution
To meet these requirements, WFFF-TV and WVNY-TV chose to deploy an
Active Power CleanSource 150 kVA UPS system to ensure continuous
availability and uptime of its transmitter signal.
Result
Active Power delivered a more reliable and cost effective solution with lower
maintenance requirements versus a legacy battery UPS. The system has
enabled the two stations to deliver on their promise of providing a high quality
product with no interruptions to their growing viewership base.
We felt CleanSource UPS was a more affordable solution with lower
maintenance than conventional battery UPS systems. We had more
than 200 power incidents over a period of six months following
installation with no interruption in service to our viewers. This
machine is just a workhorse.
– Matt Servis, Director, Engineering
Confidential and Proprietary
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